1 /* $NetBSD: unvis.c,v 1.19 2000/01/22 22:19:13 mycroft Exp $ */ 2 3 /*- 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)unvis.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: unvis.c,v 1.19 2000/01/22 22:19:13 mycroft Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #define __LIBC12_SOURCE__ 46 47 #include "namespace.h" 48 #include <sys/types.h> 49 50 #include <assert.h> 51 #include <ctype.h> 52 #include <stdio.h> 53 #include <vis.h> 54 55 #ifdef __weak_alias 56 __weak_alias(strunvis,_strunvis) 57 __weak_alias(unvis,_unvis) 58 #endif 59 60 __warn_references(unvis, 61 "warning: reference to compatibility unvis(); include <vis.h> for correct reference") 62 63 /* 64 * decode driven by state machine 65 */ 66 #define S_GROUND 0 /* haven't seen escape char */ 67 #define S_START 1 /* start decoding special sequence */ 68 #define S_META 2 /* metachar started (M) */ 69 #define S_META1 3 /* metachar more, regular char (-) */ 70 #define S_CTRL 4 /* control char started (^) */ 71 #define S_OCTAL2 5 /* octal digit 2 */ 72 #define S_OCTAL3 6 /* octal digit 3 */ 73 74 #define isoctal(c) (((u_char)(c)) >= '0' && ((u_char)(c)) <= '7') 75 76 int 77 unvis(cp, c, astate, flag) 78 char *cp; 79 int c; 80 int *astate, flag; 81 { 82 return __unvis13(cp, (int)c, astate, flag); 83 } 84 85 /* 86 * unvis - decode characters previously encoded by vis 87 */ 88 int 89 __unvis13(cp, c, astate, flag) 90 char *cp; 91 int c; 92 int *astate, flag; 93 { 94 95 _DIAGASSERT(cp != NULL); 96 _DIAGASSERT(astate != NULL); 97 98 if (flag & UNVIS_END) { 99 if (*astate == S_OCTAL2 || *astate == S_OCTAL3) { 100 *astate = S_GROUND; 101 return (UNVIS_VALID); 102 } 103 return (*astate == S_GROUND ? UNVIS_NOCHAR : UNVIS_SYNBAD); 104 } 105 106 switch (*astate) { 107 108 case S_GROUND: 109 *cp = 0; 110 if (c == '\\') { 111 *astate = S_START; 112 return (0); 113 } 114 *cp = c; 115 return (UNVIS_VALID); 116 117 case S_START: 118 switch(c) { 119 case '\\': 120 *cp = c; 121 *astate = S_GROUND; 122 return (UNVIS_VALID); 123 case '0': case '1': case '2': case '3': 124 case '4': case '5': case '6': case '7': 125 *cp = (c - '0'); 126 *astate = S_OCTAL2; 127 return (0); 128 case 'M': 129 *cp = (char)0200; 130 *astate = S_META; 131 return (0); 132 case '^': 133 *astate = S_CTRL; 134 return (0); 135 case 'n': 136 *cp = '\n'; 137 *astate = S_GROUND; 138 return (UNVIS_VALID); 139 case 'r': 140 *cp = '\r'; 141 *astate = S_GROUND; 142 return (UNVIS_VALID); 143 case 'b': 144 *cp = '\b'; 145 *astate = S_GROUND; 146 return (UNVIS_VALID); 147 case 'a': 148 *cp = '\007'; 149 *astate = S_GROUND; 150 return (UNVIS_VALID); 151 case 'v': 152 *cp = '\v'; 153 *astate = S_GROUND; 154 return (UNVIS_VALID); 155 case 't': 156 *cp = '\t'; 157 *astate = S_GROUND; 158 return (UNVIS_VALID); 159 case 'f': 160 *cp = '\f'; 161 *astate = S_GROUND; 162 return (UNVIS_VALID); 163 case 's': 164 *cp = ' '; 165 *astate = S_GROUND; 166 return (UNVIS_VALID); 167 case 'E': 168 *cp = '\033'; 169 *astate = S_GROUND; 170 return (UNVIS_VALID); 171 case '\n': 172 /* 173 * hidden newline 174 */ 175 *astate = S_GROUND; 176 return (UNVIS_NOCHAR); 177 case '$': 178 /* 179 * hidden marker 180 */ 181 *astate = S_GROUND; 182 return (UNVIS_NOCHAR); 183 } 184 *astate = S_GROUND; 185 return (UNVIS_SYNBAD); 186 187 case S_META: 188 if (c == '-') 189 *astate = S_META1; 190 else if (c == '^') 191 *astate = S_CTRL; 192 else { 193 *astate = S_GROUND; 194 return (UNVIS_SYNBAD); 195 } 196 return (0); 197 198 case S_META1: 199 *astate = S_GROUND; 200 *cp |= c; 201 return (UNVIS_VALID); 202 203 case S_CTRL: 204 if (c == '?') 205 *cp |= 0177; 206 else 207 *cp |= c & 037; 208 *astate = S_GROUND; 209 return (UNVIS_VALID); 210 211 case S_OCTAL2: /* second possible octal digit */ 212 if (isoctal(c)) { 213 /* 214 * yes - and maybe a third 215 */ 216 *cp = (*cp << 3) + (c - '0'); 217 *astate = S_OCTAL3; 218 return (0); 219 } 220 /* 221 * no - done with current sequence, push back passed char 222 */ 223 *astate = S_GROUND; 224 return (UNVIS_VALIDPUSH); 225 226 case S_OCTAL3: /* third possible octal digit */ 227 *astate = S_GROUND; 228 if (isoctal(c)) { 229 *cp = (*cp << 3) + (c - '0'); 230 return (UNVIS_VALID); 231 } 232 /* 233 * we were done, push back passed char 234 */ 235 return (UNVIS_VALIDPUSH); 236 237 default: 238 /* 239 * decoder in unknown state - (probably uninitialized) 240 */ 241 *astate = S_GROUND; 242 return (UNVIS_SYNBAD); 243 } 244 } 245 246 /* 247 * strunvis - decode src into dst 248 * 249 * Number of chars decoded into dst is returned, -1 on error. 250 * Dst is null terminated. 251 */ 252 253 int 254 strunvis(dst, src) 255 char *dst; 256 const char *src; 257 { 258 char c; 259 char *start = dst; 260 int state = 0; 261 262 _DIAGASSERT(src != NULL); 263 _DIAGASSERT(dst != NULL); 264 265 while ((c = *src++) != '\0') { 266 again: 267 switch (__unvis13(dst, c, &state, 0)) { 268 case UNVIS_VALID: 269 dst++; 270 break; 271 case UNVIS_VALIDPUSH: 272 dst++; 273 goto again; 274 case 0: 275 case UNVIS_NOCHAR: 276 break; 277 default: 278 return (-1); 279 } 280 } 281 if (__unvis13(dst, c, &state, UNVIS_END) == UNVIS_VALID) 282 dst++; 283 *dst = '\0'; 284 return (dst - start); 285 } 286